The ballon the light rope and the monkey shown in figure are at rest in the air. If the monkey reaches the top of the rope, by what distnce does the ballon descend? Mass of the ballon =M mass of the monkey =m and the length of the rope ascended by the monkey =L

Explanation

Initially the monkey and balloon are at rest. Os, the CM is at P.
When the monkey descends through a distance L the cm. will shift.

`t_0=(m+L+Mxx0)/(M+m)`
`=(mL)/(M+m)from P`
So, the balloon descenes through a distance `(mL)/(M+m)`